Expression changes of tissue inhibitor of metalloproteinase and Collagens after spinal cord injury

LI Ren-bin; YU Guang-shu; LIN Yan-bin

doi:10.3969/j.issn.2095-252X.2018.05.016

Abstract：Objective To observe the expressions of TIMP-2, Collagen I and Collagen IV after spinal cord injury to study if expression changes influence the limb locomotion of rats with spinal cord injury. Methods Sixty SD rats were randomly divided into the sham group ( n = 12 ), 3 days post-injury group ( n = 12 ), 5 days post-injury group ( n = 12 ), 7 days post-injury group ( n = 12 ) and 9 days post-injury group ( n = 12 ). The sham group underwent laminectomy. In other groups, NYU was applied to establish the spinal cord injury model. BBB score was applied to estimate the limb locomotion of rats 1 day, 3 days, 5 days, 7 days and 9 days post-injury. Immunohistochemistry was used to detect the expressions of TIMP-2, Collagen I and Collagen IV. Western blot was applied to observe the TIMP-2, Collagen I and Collagen IV protein expressions. Results ( 1 ) BBB score declined significantly when spinal injury occurred. As the time went on, BBB score increased gradually. BBB scores 7 days post-injury, 9 days post-injury were better than that of the sham group with statistical significance ( P < 0.05 ). ( 2 ) Nissl staining showed that the structure of neurons in the sham group was complete and the structure of neurons in other groups was destroyed. The structure of neurons 9 days post-injury was refined. 3. Immunohistochemistry showed that expressions of TIMP-2, Collagen I and Collagen IV in sham group were on the low levels, while in other groups TIMP-2, Collagen I and Collagen IV expressions were higher than that of the sham group with statistical significance ( P < 0.05 ). TIMP-2 expression was the highest 5 days post-injury with statistical significance ( P < 0.05 ). Collagen I and Collagen IV expressions were the highest 7 days post-injury with statistical significance ( P < 0.05 ). Conclusions Changes of limb motor function in rats of spinal cord injury may be related to the changes of TIMP-2, Collagen I and Collagen IV expressions. Expression changes are good for the limb motor function recovery.